He explained: “It’s the same as if you’re in the Amazon rainforest and you encounter a lost tribe.

“You’d include their message, or part of it, as an echo.

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ALIEN INVASION: SETI promises to make alien contact known to the public

Notable People That Have Seen UFOs or Know of Their Existence

Saturday, 24th September 2016

According to these celebrities, aliens and UFOs are among us.

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William Shatner: is a UFO believer, saying, 'There is no doubt that there is life out there; the mathematics of it lead you to that absolute conclusion. In my mind, there is no doubt that the universe teems - with life in all its form'

"But you’d need to have something simple at the front and build upon it.”

But once everyone knows about it someone will inevitably decide to send their own signal, Dr Elliot warned.

He added: “I would have thought that there would be a reply made in some form at some point round the globe by someone with the required equipment."